This Proposal has been designed to investigate arterial gene transfer of naked DNA encoding for the 165-amino acid isoform of the VEGF-1 (VEGF A) gene as an adjunct to PTCA. The Proposal has the following three Specific Aims. Specific Aim #1: to determine the safety of coronary gene transfer of phVEGF165 to accelerate re-endothelialization (rET) following percutaneous transluminal coronary angioplasty (PTCA) in patients (pts) with stenotic or occluded native coronary arteries. Specific Aim #2: to obtain preliminary data regarding bioactivity of coronary gene transfer of phVEGF165 for prevention of restonosis. Specific Aim #3: to determine the impact of phVEGF165 coronary gene transfer on the progression of atherosclerosis involving coronary arterial sites other than PTCA target sites. A variety of assessments will be performed among the patients enrolled in this study following gene transfer. Serial clinical examinations- including standard history and physical examinations-along with standard laboratory tests will be performed to document the safety of phVEGF165 coronary gene transfer. The patients' status will be further monitored by both non-invasive tests (pre- and post-exercise testing-including nuclear perfusion scans) and invasive testing )pre- and post-quantitative coronary angiopathy and intravascular ultrasound). These latter examinations will be particularly critical for addressing Specific Aims 2 and 3. It is our anticipation that the findings of this study should establish the safety- and potentially provide insights regarding efficacy- that would help to guide decisions regarding the value of testing this proposed therapeutic strategy further in Phase II trials.